AU2015273208B2 - Methods of copper extraction - Google Patents
Methods of copper extraction Download PDFInfo
- Publication number
- AU2015273208B2 AU2015273208B2 AU2015273208A AU2015273208A AU2015273208B2 AU 2015273208 B2 AU2015273208 B2 AU 2015273208B2 AU 2015273208 A AU2015273208 A AU 2015273208A AU 2015273208 A AU2015273208 A AU 2015273208A AU 2015273208 B2 AU2015273208 B2 AU 2015273208B2
- Authority
- AU
- Australia
- Prior art keywords
- copper
- ore
- aqueous solution
- concentrate
- ammonium
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Ceased
Links
- 239000010949 copper Substances 0.000 title claims abstract description 259
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 title claims abstract description 257
- 229910052802 copper Inorganic materials 0.000 title claims abstract description 257
- 238000000034 method Methods 0.000 title claims abstract description 123
- 238000000605 extraction Methods 0.000 title abstract description 20
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims abstract description 138
- 238000002386 leaching Methods 0.000 claims abstract description 121
- 239000007864 aqueous solution Substances 0.000 claims abstract description 85
- 239000002253 acid Substances 0.000 claims abstract description 75
- 229910021529 ammonia Inorganic materials 0.000 claims abstract description 66
- 230000008569 process Effects 0.000 claims abstract description 59
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 claims abstract description 56
- 239000012141 concentrate Substances 0.000 claims description 105
- 239000007787 solid Substances 0.000 claims description 79
- 150000001879 copper Chemical class 0.000 claims description 74
- 239000000243 solution Substances 0.000 claims description 56
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims description 20
- 229910001882 dioxygen Inorganic materials 0.000 claims description 20
- 239000012530 fluid Substances 0.000 claims description 17
- DVRDHUBQLOKMHZ-UHFFFAOYSA-N chalcopyrite Chemical compound [S-2].[S-2].[Fe+2].[Cu+2] DVRDHUBQLOKMHZ-UHFFFAOYSA-N 0.000 claims description 12
- 229910052951 chalcopyrite Inorganic materials 0.000 claims description 12
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 claims description 10
- 229910052921 ammonium sulfate Inorganic materials 0.000 claims description 10
- 235000011130 ammonium sulphate Nutrition 0.000 claims description 10
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 claims description 6
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 5
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 5
- 238000011065 in-situ storage Methods 0.000 claims description 5
- PAWQVTBBRAZDMG-UHFFFAOYSA-N 2-(3-bromo-2-fluorophenyl)acetic acid Chemical compound OC(=O)CC1=CC=CC(Br)=C1F PAWQVTBBRAZDMG-UHFFFAOYSA-N 0.000 claims description 3
- 235000019270 ammonium chloride Nutrition 0.000 claims description 3
- 239000000908 ammonium hydroxide Substances 0.000 claims description 3
- ATRRKUHOCOJYRX-UHFFFAOYSA-N Ammonium bicarbonate Chemical compound [NH4+].OC([O-])=O ATRRKUHOCOJYRX-UHFFFAOYSA-N 0.000 claims description 2
- 239000001099 ammonium carbonate Substances 0.000 claims description 2
- 235000012501 ammonium carbonate Nutrition 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 claims description 2
- 230000003750 conditioning effect Effects 0.000 abstract description 53
- 230000003213 activating effect Effects 0.000 abstract description 43
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 18
- 229910052760 oxygen Inorganic materials 0.000 description 18
- 239000001301 oxygen Substances 0.000 description 18
- 229910052500 inorganic mineral Inorganic materials 0.000 description 12
- 239000011707 mineral Substances 0.000 description 12
- 150000001875 compounds Chemical class 0.000 description 11
- 239000005749 Copper compound Substances 0.000 description 10
- 150000001880 copper compounds Chemical class 0.000 description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 10
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 9
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical compound [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 description 8
- 239000003153 chemical reaction reagent Substances 0.000 description 8
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 7
- -1 chrysolcolla Inorganic materials 0.000 description 7
- 238000011084 recovery Methods 0.000 description 7
- 238000004090 dissolution Methods 0.000 description 6
- 239000000203 mixture Substances 0.000 description 6
- JJLJMEJHUUYSSY-UHFFFAOYSA-L Copper hydroxide Chemical class [OH-].[OH-].[Cu+2] JJLJMEJHUUYSSY-UHFFFAOYSA-L 0.000 description 5
- 239000007789 gas Substances 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 4
- BERDEBHAJNAUOM-UHFFFAOYSA-N copper(I) oxide Inorganic materials [Cu]O[Cu] BERDEBHAJNAUOM-UHFFFAOYSA-N 0.000 description 4
- OMZSGWSJDCOLKM-UHFFFAOYSA-N copper(II) sulfide Chemical compound [S-2].[Cu+2] OMZSGWSJDCOLKM-UHFFFAOYSA-N 0.000 description 4
- 229960004643 cupric oxide Drugs 0.000 description 4
- 238000000638 solvent extraction Methods 0.000 description 4
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 3
- 229910001956 copper hydroxide Inorganic materials 0.000 description 3
- 238000005363 electrowinning Methods 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 229910000069 nitrogen hydride Inorganic materials 0.000 description 3
- 239000007800 oxidant agent Substances 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 108091005950 Azurite Proteins 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 2
- 239000005750 Copper hydroxide Substances 0.000 description 2
- 239000005751 Copper oxide Substances 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 241000907663 Siproeta stelenes Species 0.000 description 2
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical group [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 2
- 238000005273 aeration Methods 0.000 description 2
- 150000003863 ammonium salts Chemical class 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 229910052948 bornite Inorganic materials 0.000 description 2
- 229910052947 chalcocite Inorganic materials 0.000 description 2
- 230000001143 conditioned effect Effects 0.000 description 2
- 229910000431 copper oxide Inorganic materials 0.000 description 2
- ROCOTSMCSXTPPU-UHFFFAOYSA-N copper sulfanylideneiron Chemical class [S].[Fe].[Cu] ROCOTSMCSXTPPU-UHFFFAOYSA-N 0.000 description 2
- NFFYXVOHHLQALV-UHFFFAOYSA-N copper(iii) oxide Chemical compound [O-2].[O-2].[O-2].[Cu].[Cu] NFFYXVOHHLQALV-UHFFFAOYSA-N 0.000 description 2
- GEZOTWYUIKXWOA-UHFFFAOYSA-L copper;carbonate Chemical compound [Cu+2].[O-]C([O-])=O GEZOTWYUIKXWOA-UHFFFAOYSA-L 0.000 description 2
- AEJIMXVJZFYIHN-UHFFFAOYSA-N copper;dihydrate Chemical compound O.O.[Cu] AEJIMXVJZFYIHN-UHFFFAOYSA-N 0.000 description 2
- LBJNMUFDOHXDFG-UHFFFAOYSA-N copper;hydrate Chemical compound O.[Cu].[Cu] LBJNMUFDOHXDFG-UHFFFAOYSA-N 0.000 description 2
- KRFJLUBVMFXRPN-UHFFFAOYSA-N cuprous oxide Chemical compound [O-2].[Cu+].[Cu+] KRFJLUBVMFXRPN-UHFFFAOYSA-N 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 2
- 238000009854 hydrometallurgy Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000011435 rock Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 150000004763 sulfides Chemical class 0.000 description 2
- 229910052717 sulfur Inorganic materials 0.000 description 2
- 239000011593 sulfur Substances 0.000 description 2
- GWBUNZLLLLDXMD-UHFFFAOYSA-H tricopper;dicarbonate;dihydroxide Chemical compound [OH-].[OH-].[Cu+2].[Cu+2].[Cu+2].[O-]C([O-])=O.[O-]C([O-])=O GWBUNZLLLLDXMD-UHFFFAOYSA-H 0.000 description 2
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 description 1
- 244000228957 Ferula foetida Species 0.000 description 1
- 239000007832 Na2SO4 Substances 0.000 description 1
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 238000013019 agitation Methods 0.000 description 1
- 150000003868 ammonium compounds Chemical class 0.000 description 1
- JEMGLEPMXOIVNS-UHFFFAOYSA-N arsenic copper Chemical compound [Cu].[As] JEMGLEPMXOIVNS-UHFFFAOYSA-N 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 125000005587 carbonate group Chemical group 0.000 description 1
- 239000012159 carrier gas Substances 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 239000013626 chemical specie Substances 0.000 description 1
- 229940116318 copper carbonate Drugs 0.000 description 1
- BUGICWZUDIWQRQ-UHFFFAOYSA-N copper iron sulfane Chemical compound S.[Fe].[Cu] BUGICWZUDIWQRQ-UHFFFAOYSA-N 0.000 description 1
- BWFPGXWASODCHM-UHFFFAOYSA-N copper monosulfide Chemical compound [Cu]=S BWFPGXWASODCHM-UHFFFAOYSA-N 0.000 description 1
- 229910052955 covellite Inorganic materials 0.000 description 1
- 229940112669 cuprous oxide Drugs 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 150000002009 diols Chemical class 0.000 description 1
- 229910052971 enargite Inorganic materials 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 238000001033 granulometry Methods 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 229910052738 indium Inorganic materials 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 229910021506 iron(II) hydroxide Inorganic materials 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 229910052752 metalloid Inorganic materials 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229960003903 oxygen Drugs 0.000 description 1
- 239000010970 precious metal Substances 0.000 description 1
- 239000000047 product Substances 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 229910052938 sodium sulfate Inorganic materials 0.000 description 1
- 239000011343 solid material Substances 0.000 description 1
- 229910052569 sulfide mineral Inorganic materials 0.000 description 1
- 235000011149 sulphuric acid Nutrition 0.000 description 1
- 229910052970 tennantite Inorganic materials 0.000 description 1
- VZGDMQKNWNREIO-UHFFFAOYSA-N tetrachloromethane Chemical compound ClC(Cl)(Cl)Cl VZGDMQKNWNREIO-UHFFFAOYSA-N 0.000 description 1
- 229910052969 tetrahedrite Inorganic materials 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B15/00—Obtaining copper
- C22B15/0063—Hydrometallurgy
- C22B15/0065—Leaching or slurrying
- C22B15/0078—Leaching or slurrying with ammoniacal solutions, e.g. ammonium hydroxide
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B1/00—Preliminary treatment of ores or scrap
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B15/00—Obtaining copper
- C22B15/0002—Preliminary treatment
- C22B15/001—Preliminary treatment with modification of the copper constituent
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B15/00—Obtaining copper
- C22B15/0063—Hydrometallurgy
- C22B15/0065—Leaching or slurrying
- C22B15/0067—Leaching or slurrying with acids or salts thereof
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B15/00—Obtaining copper
- C22B15/0063—Hydrometallurgy
- C22B15/0065—Leaching or slurrying
- C22B15/0067—Leaching or slurrying with acids or salts thereof
- C22B15/0071—Leaching or slurrying with acids or salts thereof containing sulfur
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B15/00—Obtaining copper
- C22B15/0063—Hydrometallurgy
- C22B15/0084—Treating solutions
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
- C22B3/04—Extraction of metal compounds from ores or concentrates by wet processes by leaching
- C22B3/06—Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic acid solutions, e.g. with acids generated in situ; in inorganic salt solutions other than ammonium salt solutions
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
- C22B3/04—Extraction of metal compounds from ores or concentrates by wet processes by leaching
- C22B3/06—Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic acid solutions, e.g. with acids generated in situ; in inorganic salt solutions other than ammonium salt solutions
- C22B3/08—Sulfuric acid, other sulfurated acids or salts thereof
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
- C22B3/04—Extraction of metal compounds from ores or concentrates by wet processes by leaching
- C22B3/12—Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic alkaline solutions
- C22B3/14—Extraction of metal compounds from ores or concentrates by wet processes by leaching in inorganic alkaline solutions containing ammonia or ammonium salts
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B3/00—Extraction of metal compounds from ores or concentrates by wet processes
- C22B3/20—Treatment or purification of solutions, e.g. obtained by leaching
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C9/00—Alloys based on copper
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Abstract
The hydrometallurgical copper extraction processes of the present teachings generally Including two steps: a conditioning or activating step using low concentrations of ammonia and ammonium in an aqueous solution; and an acid leaching step. The processes of the present teachings can he performed at low temperature, for example, at ambient temperature, and at atmospheric pressure.
Description
METHODS OF COPPER EXTRACTION
FIELD
The present teachings relate to copper extraction and recovery processes. More specifically, the present teachings relate to hydrometallurgical copper extraction processes,
BACKGROUND
Pure copper is rarely found in nature. Instead copper is usually combined with other elements in copper ores. Over a dozen copper ores are mined commercially around the world. Sulfide ores, in which copper is bonded to sulfur, are the most 10 common. Other copper ores include oxide ores, carbonate ores, and mixed ores.
The processes for extracting copper from a copper ore varies according to the type of ore, the desired purity level of the final product, and other factors, Each process typically includes a series of steps during which unwanted components are removed physically, chemically and/or electrochemically, with the purity of copper increasing 15 during the process. The first step often is the physical concentration of a copper ore into a copper concentrate, in which the level of copper can be increased from a few percent up io about 20% to 30%.
The extraction processes can be hydrometallurgical or pyrometallurgical, Hydrometallurgical processing of copper ores often results in incomplete recovery of 20 copper and other precious metals, long cycle times, poor product quality, and the difficulty in disposal and/or treatment of reagents and by-products of the aqueous processes. Alternative copper extraction processes, particularly for refractory materials such as chalcopyrite or copper concentrates, can be conducted at high temperatures, under high pressure (e.g., an increased partial pressure of oxygen), and/or with strong 25 chemical oxidants or expensive reagents.
WO 2015/189707
PCT/IB2015/001706
Chalcopyrite (CuFeS?) is one of the most abundant copper-bearing minerals, which accounts for approximately 70 percent of the world’s known copper reserves. For more than 30 years, a significant number of processes have been developed to leach copper from chalcopyrite. A number of demonstration plant operations have been conducted, but none of the processes have become completely commercially operational. During the past decades, there has been a decline in copper grades, often remarked upon as a future challenge to the copper industry. The decline in ore grades is projected to continue and, in addition, ore mineralogy would become more complex. The need to process low-grade and/or complex chalcopyrite-containing ores has been the main driver for the development of hydrometallurgical processes.
Thus, there is a need io improve the hydrometallurgical extraction of copper from copper ores and copper concentrates.
SUMMARY
In light of the foregoing, the present teachings provide methods of extracting and of recovering copper from a copper ore or a copper concentrate that can address various deficiencies and/or shortcomings of the state-of-the-art, including those outlined above. In particular, unlike ammonia leaching processes that dissolve copper into solution, the processes of the present teachings can condition or activate a copper ore or a copper concentrate, using an aqueous solution that includes a concentration of ammonia and ammonium insufficient to dissolve directly a significant amount of the copper content in the copper ore or the copper concentrate. Copper can be recovered from the conditioned or activated copper ore or copper concentrate using standard acid leaching processes followed by standard copper recovery downstream operations such as solvent extraction and electrowinning.
More specifically, the copper extraction processes of the present teaching can be applicable to various copper ores and minerals such as low-grade and chalcopyritecontaining ores and generally including two steps: a conditioning or activating step; and an. acid leaching step. Processes of the present teachings can be performed at. lo w
WO 2015/189707
PCT/IB2015/001706 temperature, for example, at ambient temperature or about 30 °C. Processes of the present teachings can be performed at atmospheric pressure, In addition to these mild processing conditions, the processes of the present teachings generally do not require expensive reagents or strong chemical oxidants. Rather, low concentrations of relatively inexpensive and readily available reagents can be used. For example, the processes of the present teachings can permit the high yield extraction and recovery of copper from high percentage chalcopyrite-containing ores at a relatively high rate.
Thus, in one aspect, the present teachings provide methods of extracting copper from a copper ore or a copper concentrate. The methods generally include a conditioning or activating step such as contacting a copper ore or a copper concentrate with an aqueous solution comprising ammonia and ammonium in the presence of an oxygen gas-containing fluid such as air to provide a (solid) activated copper ore or a (solid) activated copper concentrate; and an acid leaching step such as leaching with an acid the solid activated copper ore or the solid activated copper concentrate to provide a pregnant leaching solution, The methods can include recovering the copper from the pregnant leaching solution.
In various embodiments, the conditioning or activating step of the methods of the present teachings can include contacting at a temperature less than about 50 °C a copper ore or a copper concentrate with an aqueous solution comprising ammonia and ammonium in the presence of an oxygen gas-containing fluid to provide an activated copper ore or an activated copper concentrate, which activated copper ore or activated copper concentrate can be subjected to an acid leaching process.
In some embodiments, the conditioning or activating step of the methods of the present teachings can include contacting a copper ore or a copper concentrate with an aqueous solution comprising ammonia and ammonium in the presence of an oxygen gas-containing fluid to provide an activated copper ore or an activated copper concentrate, where the aqueous solution has a pH between about 8 to about 10. The
WO 2015/189707
PCT/IB2015/001706 activated copper ore or the activated copper concentrate then can be subjected to an acid leaching process.
In certain embodiments, the conditioning or activating step of the methods of the present teachings can include contacting at atmospheric pressure a copper ore or a copper concentrate with an aqueous solution comprising ammonia and ammonium in the presence of an oxygen gas-containing fluid to provide a solid activated copper ore or a solid activated copper concentrate, which solid activated copper ore or a solid activated copper concentrate can be subjected to an acid leaching process,
In various embodiments, the methods of the present teachings can include repeating the conditioning or activating step and the acid leaching step. For example, the methods can include collecting the solids remaining after leaching with an acid; repeating the contacting step with the collected solids to provide activated solids; and leaching with an acid the activated solids to provide another pregnant leaching solution.
In some embodiments, the methods of the present teachings can include separating the solid activated ore or the solid activated copper concentrate from the aqueous solution comprising ammonia and ammonium. The separated aqueous solution comprising ammonia and ammonium then can be reused in another contacting step with another copper ore or another copper concentrate, or with the collected solids remaining after leaching an activated copper ore or concentrate with an acid. In such methods, the separated or recovered aqueous solution can be reused several times without any substantial changes to the solution, other than eventual addition of reagents and/or water to replenish the solution to its original condition.
In another aspect, the present teachings include copper recovered from or using a process as taught and described herein as well as articles of manufacture made with the copper recovered from or using a process as taught and described herein.
WO 2015/189707
PCT/IB2015/001706
The foregoing as well as other features and advantages of the present teachings will be more fully understood from the following figures, description, examples, and claims.
DESCRIPTION OF DRAWING
It should be understood that the drawing described below is for illustration purposes only. The drawing is not intended to limit the scope of the present teachings in any way
Figure 1 is a graph of the percentage of copper extracted from a highly chalcopyritic ore using an embodiment of the process of the present teachings (triangles) compared to a standard acid leaching process (squares).
DETAILED DESCRIPTION
It now has been discovered that copper can be hydronietallurgically extracted from, copper ores and copper concentrates, and particularly from low-grade and/or complex chalcopyritic-containing ores, under mild conditions and using readily available and relatively inexpensive reagents including ammonium salts. That is, the present teachings provide methods or processes for the extraction and/or recovery of copper from copper ores and from copper concentrates using an aqueous solution to condition or activate the copper ore or the copper concentrate; and an acid leach of the activated copper ore or the activated copper concentrate to create a pregnant leaching solution.
More specifically, the present teachings provide methods or processes for the extraction and/or recovery of copper from copper ores and from copper concentrates using a multi-step process. In a (first) conditioning or activating step, an aqueous solution including low concentrations of ammonia and ammonium can contact a copper ore or a copper concentrate io provide a solid activated copper ore or a solid activated copper concentrate. The solid activated copper ore or the solid activated copper concentrate then can be subjected to leaching with an acid to provide a pregnant
WO 2015/189707
PCT/IB2015/001706 leaching solution. Finally, the methods can include recovering the copper from the pregnant leaching solution.
The processes of the present teachings can he applied or used in diverse operational contexts and processes such as dump leaching, heap leaching, in situ leaching, tank leaching, vat leaching, and concentrates leaching.
Throughout the application, where compositions are described as having, including, or comprising specific components, or where processes are described as having, including, or comprising specific process steps, it is contemplated that compositions of the present teachings also consist essentially of, or consist of, the recited components, and that the processes of the present teachings also consist essentially of, or consist of, the recited process steps.
In the application, where an element or component is said to be included in and/or selected from, a list of recited elements or components, it should be understood that the element or component can be any one of the recited elements or components, or the element or component can be selected from a group consisting of two or more of the recited elements or components. Further, it should be understood that elements and/or features of a composition, an apparatus, or a method described herein can be combined in a variety of ways without departing from the spirit and scope of the present teachings, whether explicit or implicit herein. For example, where reference is made to a particular structure, that structure can be used in various embodiments of apparatus of the present teachings and/or in methods of the present teachings, unless otherwise understood from, the context.
It should be understood that the expression “at least one of5 includes individually each of the recited objects after the expression and the various combinations of two or more of the recited objects unless otherwise understood from the context and use.
WO 2015/189707
PCT/IB2015/001706
The use of the term “include,” “includes,” “including,” “have,” “has,” “having,” “contain,” “contains,” or “containing,” including grammatical equivalents thereof, should be understood generally as open-ended and non-limiting, for example, not. excluding additional unrecited elements or steps, unless otherwise specifically stated or understood from the context.
The use of the singular herein, for example, “a,” “an,” and “the,” includes the plural (and vice versa) unless specifically stated otherwise.
Where the use of the term “about” is before a quantitative value, the present teachings also include the specific quantitative value itself, unless specifically stated otherwise. As used herein, the term “about” refers to a ±10% variation from the nominal value unless otherwise indicated or inferred.
It should be understood that, the order of steps or order for performing certain actions is immaterial so long as the present teachings remain operable. Moreover, two or more steps or actions may be conducted simultaneously.
At various places in the present specification, values are disclosed in groups or in ranges. It is specifically intended that the description include each and every individual subcombi nation of the members of such groups and ranges and any combination of the various endpoints of such groups or ranges. For example, an integer in the range of 0 to 40 is specifically intended to individually disclose 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, and 40, and an integer in the range of 1 to 20 is specifically intended to individually disclose 1,2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20.
The use of any and all examples, or exemplary language herein, for example, “such as” or “including,” is intended merely to illustrate better the present teachings and does not pose a limitation on the scope of the invention unless claimed. No language in
WO 2015/189707
PCT/IB2015/001706 the specification should be construed as indicating any non-claimed element as essential to the practice of the present teachings.
As used herein, an “ore” refers to a type of rock that contains minerals with elements including metals that can be economically extracted from the rock.
A “copper ore” refers to an ore that includes a copper compound including pure copper. Examples of copper ores include sulfide ores ( which contain a copper sulfide), oxide ores (which contain a copper oxide), carbonate ores (which contain copper carbonate), and mixed ores.
As used herein, a “copper concentrate” refers to a copper ore that has been crushed, milled and concentrated to provide an increased amount or percentage of copper in the resulting material than found in the original ore(s).
As used herein, a “copper compound” refers to the various minerals that include copper as an element and can refer copper as a pure metal, unless the context dictates otherwise. Examples of minerals including copper are atacamite, azurite, bornite, chalcocite, chalcopyrite, chrysolcolla, covellite, cuprite, malachite, tennantite, and tetrahedrite.
As used herein, a “copper carbona te” refers to one or more members of a family of chemical compounds and minerals where the compound or mineral contains the element copper associated with a carbonate group. Examples of copper carbonates include malachite (CuCOHh’CuCOj), a green powder; and azurite (Cu(OH)2-2CuCO3), a blue powder.
As used herein, a “copper sulfide” refers to one or more members of a family of chemical compounds and minerals with the formula CuxSv, including mixed coppermetal sulfides and mixed copper-metalloid sulfides containing copper and sulfur such as mixed copper-iron sulfides and mixed copper-arsenic sulfides. Examples of copper sulfide minerals include chalcocite (Cu2S) and covellite (CuS) and the minerals, bornite
WO 2015/189707
PCT/IB2015/001706 (2Cu2S-CuS-FeS) and chalcopyrite (CuFeS2), which are mixed copper-iron sulfides, and enargite (CujAsS*), which is a mixed copper-arsenic sulfide.
As used herein, a “copper oxide” refers to one or more members of family of chemical compounds and minerals where the compound or mineral contains the element copper associated with oxygen. Examples of copper oxides include cuprite (Cu2O (cuprous oxide)), a red powder; cupric oxide (CuO), a black powder; and copper (III) oxide (CU2O3).
As used herein, an “oxygen gas-containing fluid” refers to liquid and/or gas including oxygen gas or dissolved oxygen. An oxygen gas-containing fluid can be an oxy gen-containing gas such as air or gaseous oxygen, both of which can be with another carrier gas or liquid. An oxygen gas-containing fluid can be an oxygenated liquid such as oxygenated water or water including dissolved oxygen. The source of dissolved oxygen can be the surrounding air, which can be at atmospheric pressure.
As described herein, copper extraction processes of the present teachings generally include two steps; a first conditioning or activating step; and a second acid leaching step. The conditioning or activating of a copper ore or copper concentrate can provide a solid activated copper ore or a solid activated copper concentrate, which activated solids can be leached with acid to provide a pregnant leaching solution. Copper then can be recovered from the pregnant leaching solution.
More specifically, the conditioning or activating step can include contacting a copper ore or a copper concentrate with an aqueous solution comprising ammonia and ammonium in the presence o f an oxygen gas-containing fluid to provide a (solid) activated copper ore or a (solid) activated copper concentrate.
Unlike ammoni a leaching processes, the conditioning of the copper ore or the copper concentrate includes using an aqueous solution that includes a concentration of ammonia and ammonium insufficient to dissolve directly more than a majority of the copper and/or copper compounds in the copper ore or the copper concentrate. For
WO 2015/189707
PCT/IB2015/001706 example, the aqueous solution can include a concentration of ammonia and ammonium insufficient to dissolve directly more than about 40% of the copper recovered from the copper ore or the copper concentrate. In certain embodiments, the aqueous solution can include a concentration of ammonia and ammonium insufficient to dissolve directly more than about 30%, more than about 25%, more than about 20%, more than about 15%, more than about 10%, more than about 8%, more than about 5%, more than about 3%, more than about 2%, or less of the copper recovered from the copper ore or the copper concentrate. In certain embodiments, the aqueous solution includes a concentration of ammonia and ammonium insufficient to dissolve directly more than 25%, more than 20%, or more than 15% of the copper recovered from the copper ore or the copper concentrate.
Because copper is not soluble at a pH higher than about 5, the dissolution of copper at higher pH’s such as between a pH of 6 to 10 can be accomplished by the formation of complexes, for example, with ammonia. Any copper dissolved in an aqueous solution containing ammonia and ammonium at a pH of 9 would be complexed with ammonia. The use of the term “directly” in relation to dissolution of copper refers to the conditions present during the step of the process or method in which this term Is used. For example, if the aqueous solution including ammonia and ammonium can dissolve directly no more than 20% of the copper recovered in the process, then the aqueous solution can dissolve no more than 20% of the recovered copper in the step in which the aqueous solution is being used, for example, in a conditioning or activating step, and does not include the dissolution of copper during other steps, for example, an acid leaching or other subsequent processing or steps.
In some embodiments of the methods of the present teachings, the aqueous solution can include between about 1 mg/L to about 40 g/L of ammonia and ammonium. In certain embodiments, the aqueous solution can include between about I mg/L to about 30 g/L, between about 1 mg/L to about 20 g/L, between about 1 mg/L to about 15 g/L, between about 1 mg/L to about 10 g/L, between about 1 mg/L to about 5 g/L, between about 1 mg/L to about 1 g/L, or between about 1 mg/L to about 500 mg/L,
WO 2015/189707
PCT/IB2015/001706 of ammonia and ammonium. In particular embodiments, the aqueous solution can include between, about 1 mg/L to about 30 g/L, between about 1 mg/L to about 20 g/L, or about 100 mg/L to about 20 g/L.
In various embodiments of the methods of the present teachings, the ammonium can be derived from one or more sources of ammonium ions, such as ammonium carbonate, ammonium chloride, ammonium hydroxide, ammonium nitrate, and ammonium sulfate. As used herein “ammonium” refers NHf or an ammonium ion, which terms and formula can be used interchangeably herein. In particular embodiments, the source of ammonium is ammonium sulfate. The source of ammonia, indirectly, can be ammonium sulfate.
It should be understood that the ammonia present in the aqueous solution can be derived from the source of ammonium. That is, free ammonia or gaseous ammonia need not be introduced into the aqueous solution used in the conditioning or activating step, but. rather the ammonia can be derived in situ from the equilibrium of the ammonium ions in the aqueous solution. As discussed in more detail herein, when ammonium, ions are in an aqueous solution, an equilibrium exists with the ammonium ions and ammonia, which equilibrium is pH dependent. Thus, upon the dissolution of the source of ammonium in water to provide, in part, the aqueous conditioning or activating solution, ammonia can be generated, which ammonia can participate in the hydrometallurgical processes.
In some embodiments, the ammonia and ammonium can be derived from gaseous ammonia delivered in an appropriate amount to water or an aqueous solution, whereby the ammonia in water forms an equilibrium between the ammonia and ammonium as described herein, which equilibrium is pH dependent.
In some embodiments of the present teachings, the conditioning or activating step can be conducted or carried out at an atmospheric pressure. In certain embodiments, the conditioning or activating step can be conducted at a higher pressure, for example, in a pressure chamber or vessel such as an autoclave. The higher or
WO 2015/189707
PCT/IB2015/001706 increased pressure can include an increased pressure of oxygen (e.g., an increased oxygen partial pressure). For example, the conditioning step can be carried out or conducted at or under an increased partial pressure of oxygen or increased oxygen partial pressure, for example, at about 5 psi, at about 10 psi, at about 15 psi, or higher of oxygen partial pressure.
The aqueous solution including ammonia and ammonium can have a pH from about 5 to about 10. In certain embodiments, the pH of the aqueous solution can be between about 5 to about 10, between about 6 to about 10, between about 6 to about 9, between about 6 io about 8, between about 7 to about 10, between about 7 to about 9, between about 7 to about 8, between about 8 to about 10, between about 8 to about 9.5, between about 8 to about 9, between about 8.5 to about 10, between about 8.5 to about 9.5, between about 8.5 to about 9, between about 9 to about 10, between about 9 to about 9.5, between about 6 to about 10, or between about 6 to about 10. In particular embodiments, the pH of the aqueous solution can be between about 8 io about 9.5, between about 8.5 to about 9.5, between about 9 to about 9.5, between about 8 to about 9, between about 8 to about 8.5, or between about 8.5 to about 9.
The pH of the aqueous solution can be adjusted, regulated and/or maintained as appropriate for the particular conditioning or activating process and other factors such as the copper ore or copper concentrate to be processed. A base such as sodium hydroxide or another alkaline compound can be used to adjust the pH of the aqueous solution. Use of a base or alkaline compound can be avoided if the ammonia and ammonium-generating reagent(s) is of sufficient alkalinity thereby providing a pH of the aqueous solution in a range as described herein for the conditioning or activating step.
In some embodiments, the conditioning or activating step can be conducted or earned out at ambient temperature. The conditioning or activating step can be conducted at a higher temperature, for example, at a temperature up to about 90 °C or about 95 °C. In some embodiments, the conditioning or activating step can be
WO 2015/189707
PCT/IB2015/001706 conducted at a temperature between about ambient temperature and about 80 °C, about 75 °C, about 70 °C, about 65 °C, about 60 °C, about 55 °C, about 50 °C, about 45 °C, about 40 °C, or between ambient temperature and about 35 °C, In certain embodiments, the conditioning or activating step can be conducted at a temperature below about 80 °C, below about 75 °C, below about 70 °C, below about 65 °C, below about 60 °C, below about 55 °C, below about 50f,C, below about 45 C'C, below about 40 °C, or below about 35 °C. It is also within the scope of the present teachings to conduct the conditioning or activating step at a temperature below ambient temperature. In particular embodiments, the conditioning or activating step is conducted at ambient temperature, at a. temperature between ambient temperature and about 90 °C, or at a temperature below about 50 °C.
fhe conditioning or activating step can be conducted or carried out in the presence of an oxygen gas-containing fluid such as an oxygen-containing gas, for example, air. The oxygen gas-containing fluid such as air can be considered a mild oxidant. ’The conditioning step is typically carried out at atmospheric pressure. Accordingly, air can be delivered to the aqueous solution, for example, under the surface of the aqueous solution such that the oxygen gas-containing gas is bubbled into and up through the aqueous solution to provide (dissolved) oxygen for this processing step. Other means for providing dissolved oxygen or oxygen gas into the aqueous solution can be used. The aeration technique can depend on the particular process and equipment being used for the conditioning or activating step (e.g., a heap or vat or reactor conditioning or activating technique or process). Accordingly, an appropriate aeration system can be used, For example, blowers can be used to provide the necessary air or oxygen into the aqueous solution. In some embodiments, the oxygen gas-containing fluid can be oxygenated water (i.e,, water containing dissolved oxygen) that can be delivered into and/or circulated through the aqueous solution. The aqueous solution typically is aerated continuously throughout the conditioning or activating step.
It should be understood that the various parameters or conditions of the conditioning or activating step, for example, temperature, pressure, pH of the aqueous
WO 2015/189707
PCT/IB2015/001706 solution including ammonia and ammonium, and the concentration of ammonia and ammonium can be varied as described herein in various combinations and values or ranges and such combinations of conditions and values or ranges thereof are within the scope of the present teac hings.
Following the conditioning or activating of the copper ore or the copper concentrate, the solid activated ore or the solid activated copper concentrate is subjected to conventional acid leaching to create or provide a pregnant leaching solution. As already stated, the processes of the present teachings are dissimilar· from ammonia leaching processes as the conditioning or activating step does not intend to solubilize the copper or copper compounds present in the copper ore or copper concentrate upon treatment with the aqueous solution including ammonia and ammonium. Rather the solid material resulting from the conditioning or activating step, i.e., the activated copper ore or activated copper concentrate (or activated solids), is subjected to acid leaching to remove the copper and copper compounds from the solid activated ore or solid activated copper concentrate.
The acid leaching step can be carried out at a pH of between about 1.5 to about 5, for example, a pH between about 3 to about 5 or between about. 2 to about 4, The acid leaching step can result in the dissolution of the copper and/or copper compounds that remained solid after the conditioning or activating step. The acid leaching step can be conducted or carried out in the presence of an oxygen gas-containing fluid, such as air or dissolved oxygen. The acid leaching solution can be aerated as appropriate for the particular equipment and techniques used.
The acid leaching step can result in a pregnant leaching solution, for example, a copper-loaded pregnant leaching solution. The pregnant leaching solution can have similar characteristics to pregnant leaching solutions from standard leaching processes. The pregnant leaching solution can have very low or trace amounts of ammonia and ammonium, which compounds can interfere with downstream solvent extraction processes or operations. Consequently, the pregnant leaching solution can be channeled
WO 2015/189707
PCT/IB2015/001706 through standard copper recovery downstream operations such as solvent extraction and electro winning -without further modification. In addition, the short cycle time of the acid leaching process can prevent the substantial dissolution of undesired chemical species, for example, iron and/or chloride. Finally, the copper then can be collected and used in standard fashion.
The acid leaching step typically is conducted on activated solids such as the activated copper ore or the activated copper concentrate, which activated solids can be separated from the aqueous solution including ammonia and ammonium, i.e., the acid leaching is carried out separate from the conditioning or activating step and solution. However, the present teachings also include the direct addition of an acid (leaching acid) into the mixture resulting from the conditioning or activating step, thereby lowering the pH of the aqueous solution in situ.
In various embodiments, the conditioning or activating and acid leaching steps or processes can be repeated or iterated one, two, three, or more times, for example, until the desired level of copper extraction is achieved. Accordingly, in some embodiments, the methods of the present teachings can further include collecting the solids remaining after leaching with an acid; repeating the contacting step with the collected solids to provide activated solids; and leaching with an acid the activated solids to provide another pregnant leaching solution. This general cycle can be repeated one, two, three, four, or more times as needed or desired.
In some embodiments, where the activate copper ore or the activated copper concentrate is separated from the aqueous ammonia and ammonium solution before being subjected to acid leaching, the aqueous solution can be used again to condition or activate another copper ore or copper concentrate, or the solids remaining after the acid leaching step, where the solids from the acid leaching step are collected and contacted with the aqueous solution first used to condition or activate the copper ore or copper concentrate. Thus, in certain embodiments of the present teachings, the methods can include separating the solid activated copper ore or the solid activated copper
WO 2015/189707
PCT/IB2015/001706 concentrate from the aqueous solution comprising ammonia and ammonium, wherein the aqueous solution comprising ammonia and ammonium is reusable or reused in the contacting step with another copper ore or another copper concentrate, or with the collected solids remaining after leaching with an acid.
In the case where the aqueous solution containing ammonia and ammonium is separated from the activated solids and reused, the reused aqueous solution already should be “saturated” with a small fraction of the soluble copper complexes or copper compounds that are formed such that a reused aqueous solution should not dissolve any more copper or copper compounds present in a few or fresh copper ore or copper concentrate, or collected solids remaining from an acid leaching step, that is contacted with the reused aqueous solution.
Similar to reusing the aqueous solution containing ammonia and ammonium, an acid leaching solution also can be reused in the form of a raffinate. For example, after the acid leaching solution contacts an activated copper ore or copper concentrate to provide a pregnant leaching solution, the copper can be depleted and recovered from the pregnant leaching solution along with the removal of other unwanted materials whereby the resultant solution (or raffinate) can similar to the original acid leaching solution, which can be reused or recirculated for additional leaching.
The conditioning or activating step or process usually is conducted or earned out over a time of about 6 hours to about a month, 6 weeks, 2 months, or more. The initial conditioning or activating step on new or unextracted copper ore or copper concentrate typically is conducted or carried out over a time of about 12 hours to about 3 days, to about 4 days, to about 5 days, to about. 6 days, to about 7 days, to about 8 days, to about 9 days, to about 10 days, to about 11 days, to about 12 days, to about 2 weeks, to about 3 weeks, to about, a month, to about 5 weeks, to about 6 weeks, or more. The acid leaching step or process usually is conducted or carried out over a time of about 30 minutes to about several hours, for example, from about one hour to about 6 hours, 12 hours, or one day, or more. Depending on the particular acid leaching process and
WO 2015/189707
PCT/IB2015/001706 equipment, cycle times can be much longer. For example, for heap leaching, a typical cycle time for acid leaching of sulfides can be up to one year, or more.
In the embodiments where the conditioning or activating and acid leaching steps are repeated, the repetition of the conditioning or activating steps can be conducted for a shorter time such as from about 3 hours to about 24 hours, for example, from about 4 hours to about 18 hours, or from about 6 hours to about 16 hours, or for about 12 hours. In such cases, the acid leaching step tends to be shorter than its initial time. That is, the repetition of the acid leaching step can occur over a time of about 30 minutes to about 3 hours, or about 1 hour to about 2 hours, or about 1 hour. It should be understood that these times should not be considered limiting because the cycle times can vary and be longer than those mentioned above depending on the particular process and equipment.
Accordingly, the entire processing time to achieve the desired extraction level of copper can be between about 1 day to about 6 to about 7 weeks; however, between about 1 day to about 6 or 8 days is more common. Again, depending on the particular processes and equipment, the entire processing time can be much longer, for example, up to a month, a few months, several months, a year, a few years, or more,
In various embodiments, the present teachings provide methods of extracting copper that include contacting a copper ore or a copper concentrate with an aqueous solution including ammonia and ammonium in the presence of air to provide a solid activated copper ore or a solid activated copper concentrate; and leaching with an acid the solid activated copper ore or the solid activated copper concentrate to provide a pregnant leaching solution, where the aqueous solution has a pH in the range of about 7 to about 10. In certain embodiments, the aqueous solution has a pH between about 8 to about 10. In particular embodiments, the aqueous solution has a pH between about 8 to about 9.5. The methods can include repeating the contacting and leaching steps with the solids recovered from the acid, leaching and/or recovering copper from the pregnant leaching solution.
WO 2015/189707
PCT/IB2015/001706
Ill some embodiments, the present teachings provide methods of extracting copper that include contacting at atmospheric pressure a copper ore or a copper concentrate with an aqueous solution including ammonia and ammonium in the presence of air to provide an activated copper ore or an activated copper concentrate; and leaching with an acid the activated copper ore or the activated copper concentrate to provide a pregnant leaching solution, where the aqueous solution has a pH in the range of about 8 to about 10. The methods can include repeating the contacting and leaching steps with the solids recovered from the acid leaching and/or recovering copper from the pregnant leaching solution.
In certain embodiments, the present teachings provide methods of extracting copper that include contacting at atmospheric pressure in a temperature range between ambient temperature and about 90 °C a copper ore or a copper concentrate with an aqueous solution including ammonia and ammonium in the presence of air to provide an activated copper ore or an activated copper concentrate; and leaching with an acid the activated copper ore or the activated copper concentrate io provide a pregnant leaching solution, where the aqueous solution has a pH in the range of about 8 to about 10, The methods can include repeating the contacting and leaching steps with the solids recovered from the acid leaching and/or recovering copper from the pregnant leaching solution.
In particular embodiments, the present teachings provide methods of extracting copper that include contacting at atmospheric pressure at a temperature less than about 50 °C a copper ore or a copper concentrate with an aqueous solution including ammonia and ammonium, in the presence of air to provide an activated copper ore or an activated copper concentrate; and leaching with an acid the activated copper ore or the activated copper concentrate to provide a pregnant leaching solution, where the aqueous solution has a pH in the range of about 8 to about 10. The methods can include repeating the contacting and leaching steps with the solids recovered from the acid leaching and/or recovering copper from the pregnant leaching solution.
WO 2015/189707
PCT/IB2015/001706
As described herein, the present teachings include a copper extraction process that can be generally carried out in two steps, Step 1, a conditioning step, can include conditioning a copper ore or a copper concentrate with ammonium and ammonia at low concentrations, which are insufficient to allow the formation of substantial amounts of soluble copper ammoniacal complexes, carried out at neutral or slightly alkaline pH (e.g., a pH range from about 6 to about 10, such as a pH between 8 and 9.5). The conditioning solution can include an ammonium compound in a concentration range of from about 1 mg/L to about 20 g/L or up to about 150 g/L. The source of ammonium can include ammonium sulfate, ammonium chloride, ammonium nitrate, ammonium hydroxide, and combinations thereof. Sodium hydroxide (or another alkaline compound) can be used to adjust the pH. The amount used can depend on the consumption of hydroxide by the treated mineral.
Without wishing to be bound to any particular theory, in the first conditioning or activating step, it is believed that the copper in the form of a primary sulfide (e.g.. chalcopyrite), is extracted by the ammoniacal solution, but due to the low concentration of ammonia (insufficient substantially to form soluble copper complexes), the copper is not in a soluble state in the pregnant leaching solution (“PLS”), but instead in a solid state in the form of compounds that are insoluble in almost-neutral or alkaline pH solutions, such as copper hydroxides, copper oxides, and possibly other compounds.
The hydroxides, oxides or other solid copper compounds generated, although insoluble at almost-neutral or alkaline pH, are extremely soluble at acidic pH (e.g., below pH 4). For this reason, after the first step is completed, the copper can be recovered in a soluble form by relatively conventional acid leaching, which is step 2 of the extraction process.
Step 2, a conventional or standard acid leaching step, can be carried out at a pH of about 0.5 to about 5, which can solubilize the copper that was conditioned or activated in the first step, which copper is believed to be in the form of hydroxide, an oxide, or another solid copper compound that is very soluble in acid. The acid leaching
WO 2015/189707
PCT/IB2015/001706 step can be characterized by very rapid kinetics (with a cycle time significantly lower (or faster) than step 1), The result obtained is a PLS with a high concentration of copper, very similar to the PLS from conventional acid leaching processes, and with very low amounts or traces of ammonium and ammonia, which could interfere with die downstream operation of solvent extraction and electrowinning (“SX-EW”).
Without wishing to be bound by any particular theory, the following discussion is intended to illustrate a possible mechanism explaining the phenomena of the present teachings, without attempting to describe the only chemical reactions involved.
During step 1 of the process of the present teachings, the copper present as a copper sulfide can be extracted in the form of insoluble copper hydroxide, for example, according to the following proposed equation:
CuFeSs + 4NaOH + NH3 (aq) + 4 O2---> Cu(OH)2 (s) + Fe(OH)2 (s) + 2 Na2SO4 (aq) + NH3 (aq)
The reaction is catalyzed by the limiting aqueous ammonia, which is neither consumed nor generated in the context of the reaction. Obviously, ammonia is a gas, so that, despite being highly soluble in water, it evaporates, which constitutes a potential source of reagent loss. However, when conducted in a closed environment process or a closed environment such as in a reactor, the ammonia can be recovered.
In the aqueous conditioning solution, ammonia (NH3) and ammonium (NH/) are in equilibrium, according to the following equilibrium equation:
Nkh' + OH’ NH., (aq)
This equilibrium is, in turn, strongly influenced by pH. Thus, at a pH slightly above 9, the ratio of ammonium/ammonia is about 50:50; and at pH slightly above 8, the ratio changes to 90:10 (with very little ammonia and, thus, a very low evaporation rate, especially considering the low total concentration of ammonium salts used in the process).
WO 2015/189707
PCT/IB2015/001706
During step 2 of the process of the present teachings, the copper hydroxide generated in step 1 is dissolved in an acid medium, according to the following equation (with net consumption of acid (protons)):
Cu(OH)2 (s) + H2SO4 (aq) ---- Cu2+ + SOX + 2 H2O
The following examples are provided to illustrate further and to facilitate the understanding of the present teachings and are not in any way intended to limit the invention.
Example 1. Copper Extraction from Highly Chalcopyritic Ore
The copper ore was a lo w copper grade, highly chalcopyritic ore, characterized by a total copper content of 0.41%, being 88% of the copper present in the form of chalcopyrite. The granulometry of the copper ore was brought to 100% -150 Tyler Mesh,
In a one liter Erlenmeyer flask, 120 g of the copper ore was mixed with 400 mL of an ammonium sulfate solution containing 10 g/L ammonium sulfate at a pH of 9.4. The pH of the ammonium sulfate solution was adjusted to 9.4 by addition of sodium hydroxide. The mixture was reacted at 30 °C with mild agitation on an orbital shaker incubator for 2 days (step 1).
A t the end of the reaction period, sulfuric acid was added to the mixture to adjust the pH to 2.5 and standard acid leaching was performed (step 2). The acidified slurry was maintained under the same conditions described above for 2 additional hours, after which the resulting pregnant leaching solution was separated from, the solid residue by filtration. A sample of the resulting pregnant leaching solution was analyzed for copper content
The above process was repeated where the conditioning or activating step, i.e., step 1, was conducted for 4 days, 6 days, 8 days, 10 days, and 12 days, respectively. The results of the copper extraction are shown in Table 1 below and in Figure 1,
WO 2015/189707
PCT/IB2015/001706
Also shown in 'fable 1 and in Figure 1 are the results of copper extraction obtained by running a parallel set of standard acid leaching using a sulfuric acid solution at a pH range between 1.8 and 2.2, where the standard acid leaching was conducted for 2 days, 4 days, 6 days. 8 days, 10 days, and 12 days, respectively.
Table 1
Time (diol | % Copper extracted (conditioning and acid leaching) | (acid leaching only) |
0 | 0 | 0 |
2 | 42 ............... | 21 |
4 | 46 | 23 |
6 | 55 | 27 |
8 | 58 | .............................25 |
10 | 64 | 28 |
12 | 68 | 31 |
In addition, prior to step 2, i.e., the addition of the sulfuric acid to the conditioning solution, a sample of the aqueous solution containing ammonium sulfate (separated from the activated and other solids by centrifugation) was analyzed for copper content. The copper dissolved in the aqueous solution containing ammonium sulfate after the conditioning step was less than 5% of the copper recovered from the copper ore or copper concentrate. Thus, the majority of the copper was dissolved during the standard acid leaching step rather than during the conditioning or activating step.
It should be understood that the immediately above percentage is based on the amount of copper recovered from the process, which is distinct from the percentage of copper extracted from the copper ore or copper concentrate as determined in Table 1. That is, a percentage of copper extracted is based on the total copper content of the copper ore, copper concentrate or treated copper sample from which the copper is extracted. The percentage of copper extracted is an indicator of the performance of the process (i.e., the more copper extracted of the total copper available, the better). A percentage based on copper recovered from a copper ore or a copper concentrate such
WO 2015/189707
PCT/IB2015/001706 as during one iteration of the process (e.g., the two step process of the present teachings or a one step ammonia leaching process) can provide a indication of the amount of copper present, for example, in a solution or a step of the process.
The present teachings encompass embodiments in other specific forms without departing from the spirit or essential characteristics thereof. The foregoing embodiments are therefore to be considered in all respects illustrative rather than limiting on the present teachings described herein. Scope of the present invention is thus indicated by the appended claims rather than by the foregoing description, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced therein.
Claims (15)
1. A method of extracting copper from a copper ore or a copper concentrate, the method comprising:
contacting a copper ore or a copper concentrate with an aqueous solution comprising ammonia and ammonium in the presence of an oxygen gas-containing fluid to provide a solid activated copper ore or a solid activated copper concentrate, wherein the aqueous solution is unable to dissolve directly more than a majority by weight of the copper recovered from the copper ore or copper concentrate; and leaching the solid activated copper ore or the solid activated copper concentrate with an acid to provide a pregnant leaching solution.
2. The method of claim 1, further comprising recovering copper from the pregnant leaching solution.
3. The method of claim 1 or 2, wherein the ammonium is derived from one or more of ammonium carbonate, ammonium chloride, ammonium hydroxide, ammonium nitrate, and ammonium sulfate.
4. The method of any one of claims 1-3, wherein the ammonia is derived in situ from the ammonium.
5 leaching the solid activated copper ore or the solid activated copper concentrate with an acid to provide a pregnant leaching solution.
21. The method of claim 20, wherein the aqueous solution has a pH between about 8 to 9.5.
22. The method of claim 20 or 21, wherein contacting a copper ore or a
5. The method of any one of claims 1-4, wherein contacting a copper ore or a copper concentrate with an aqueous solution is carried out at atmospheric pressure.
6. The method of any one of claims 1-8, wherein contacting a copper ore or a copper concentrate with an aqueous solution is carried out at a temperature ranging from ambient temperature to about 90 °C.
7. The method of any one of claims 1-6, wherein the oxygen gas-containing fluid comprises air.
8. The method of any one of claims 1-7, wherein contacting a copper ore or a copper concentrate with an aqueous solution is carried out at a pH in the range of about 7 to about 10.
9. The method of any one of claims 1-7, wherein the contacting step is carried out at a pH in the range of about 8 to about 9.5.
10 copper concentrate with an aqueous solution is carried out at a temperature ranging from ambient temperature to about 90 °C.
23. The method of any one of claims 20-22, wherein contacting a copper ore or a copper concentrate with an aqueous solution is carried out at atmospheric pressure.
24. Copper recovered from the process of any one of claims 1-23.
10. The method of any one of claims 1-9, wherein the copper ore or the copper concentrate comprises chalcopyrite.
11. The method of any one of claims 1-10, wherein the solids remain after leaching with an acid, and the method further comprises:
collecting the solids remaining after leaching with an acid;
repeating the contacting with the collected solids to provide activated solids; and leaching the activated solids with an acid to provide another pregnant leaching solution.
12. The method of any one of claims 1-11, further comprising separating the solid activated copper ore or the solid activated copper concentrate from the aqueous solution comprising ammonia and ammonium, wherein the aqueous solution comprising ammonia and ammonium is reusable to contact another copper ore or another copper concentrate.
13. A method of extracting copper from a copper ore or a copper concentrate, the method comprising:
contacting a copper ore or a copper concentrate with an aqueous solution comprising ammonia and ammonium in the presence of an oxygen gas-containing fluid to provide a solid activated copper ore or a solid activated copper concentrate, wherein the ammonia is derived in situ from the ammonium; and leaching the solid activated copper ore or the solid activated copper concentrate with an acid to provide a pregnant leaching solution.
14. The method of claim 13, wherein contacting a copper ore or a copper concentrate with an aqueous solution is carried out at atmospheric pressure.
15. The method of claim 13 or 14, wherein contacting a copper ore or a copper concentrate with an aqueous solution is carried out at a pH in the range of about 7 to about 10.
16. The method of any one of claims 13-15, wherein contacting a copper ore or a copper concentrate with an aqueous solution is carried out at a temperature ranging from ambient temperature to about 90 °C.
17. A method of extracting copper from a copper ore or a copper concentrate, the method comprising:
contacting a copper ore or a copper concentrate with an aqueous solution comprising ammonia and ammonium in the presence of an oxygen gas-containing fluid to provide a solid activated copper ore or a solid activated copper concentrate, wherein the aqueous solution has a pH between about 7 to about 10 and is unable to dissolve directly more than a majority by weight of the copper recovered from the copper ore or the copper concentrate; and leaching the solid activated copper ore or the solid activated copper concentrate with an acid to provide a pregnant leaching solution.
18. The method of claim 17, wherein contacting a copper ore or a copper concentrate with an aqueous solution is carried out at atmospheric pressure.
19. The method of claim 17 or 18, wherein contacting a copper ore or a copper concentrate with an aqueous solution is carried out at a temperature ranging from ambient temperature to about 90 °C.
20. A method of extracting copper from a copper ore or a copper concentrate containing chalcopyrite, the method comprising:
2015273208 22 Jan 2020 contacting a copper ore comprising chalcopyrite or a copper concentrate comprising chalcopyrite with an aqueous solution comprising ammonia and ammonium in the presence of an oxygen gas-containing fluid to provide a solid activated copper ore or a solid activated copper concentrate; and
15 25. An article of manufacture comprising the copper of claim 24.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201462009017P | 2014-06-06 | 2014-06-06 | |
US62/009,017 | 2014-06-06 | ||
PCT/IB2015/001706 WO2015189707A1 (en) | 2014-06-06 | 2015-06-05 | Methods of copper extraction |
Publications (2)
Publication Number | Publication Date |
---|---|
AU2015273208A1 AU2015273208A1 (en) | 2017-01-19 |
AU2015273208B2 true AU2015273208B2 (en) | 2020-02-13 |
Family
ID=54288835
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
AU2015273208A Ceased AU2015273208B2 (en) | 2014-06-06 | 2015-06-05 | Methods of copper extraction |
Country Status (5)
Country | Link |
---|---|
US (2) | US9255308B2 (en) |
AU (1) | AU2015273208B2 (en) |
CL (1) | CL2016003152A1 (en) |
PE (1) | PE20170111A1 (en) |
WO (1) | WO2015189707A1 (en) |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102994747A (en) * | 2011-09-13 | 2013-03-27 | 郴州市金贵银业股份有限公司 | Technology for recovering metallic copper from high-lead copper matte |
Family Cites Families (28)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3148051A (en) | 1962-08-03 | 1964-09-08 | Ansor Corp | Process for the production of metallic copper powder and ammonium sulfate from copper sulfate solutions |
US3228765A (en) | 1964-06-24 | 1966-01-11 | Ansor Corp | Copper recovery process from anhydrous copper ammonium sulfite |
US3637371A (en) | 1967-02-10 | 1972-01-25 | Sherritt Gordon Mines Ltd | Direct pressure leaching of copper-iron sulphides |
CA902931A (en) | 1970-03-11 | 1972-06-20 | H. Lucas Bernard | Copper extraction from ammoniacal solutions |
US3744990A (en) | 1970-10-14 | 1973-07-10 | Golden Cycle Corp | Process for the beneficiation of waste copper slag by removal and recovery of its content of copper and zinc |
US3751240A (en) * | 1971-06-07 | 1973-08-07 | Banner Mining Co | Method of roasting copper sulphide concentrates and ores |
US3891522A (en) | 1972-02-28 | 1975-06-24 | Cominco Ltd | Hydrometallurgical process for treating copper-iron sulphides |
US4022866A (en) | 1972-03-07 | 1977-05-10 | The Anaconda Company | Recovery of metals |
US4043882A (en) | 1972-06-28 | 1977-08-23 | Kennecott Copper Corporation | Selective solvent extraction process for copper from nickel |
US4036639A (en) * | 1973-09-10 | 1977-07-19 | Sherritt Gordon Mines Limited | Production of copper |
US3954453A (en) | 1973-09-25 | 1976-05-04 | Porth Luis De La Pena | Recovery of copper from ammoniacal copper sulfate solution |
CA1024352A (en) * | 1974-10-17 | 1978-01-17 | Wasyl Kunda | Process for the recovery of copper and ammonium sulphate from copper-bearing mineral sulphide ores or concentrates |
US3975190A (en) | 1975-05-23 | 1976-08-17 | Sherritt Gordon Mines Limited | Hydrometallurgical treatment of nickel and copper bearing intermediates |
GB1565269A (en) | 1976-01-19 | 1980-04-16 | Parker A J | Method of treating acid soluble iron compounds of treating |
US4080419A (en) | 1976-12-10 | 1978-03-21 | The United States Of America As Represented By The Secretary Of The Interior | Foam injection leaching process for fragmented ore |
US4189461A (en) | 1977-11-30 | 1980-02-19 | Kennecott Copper Corporation | Metal leaching from concentrates using nitrogen dioxide in acids |
US4165264A (en) | 1978-06-14 | 1979-08-21 | Phelps Dodge Corporation | Ammonia leaching |
US4291920A (en) | 1980-04-30 | 1981-09-29 | Kennecott Corporation | In situ exploitation of deep set porphyry ores |
US4343773A (en) * | 1981-01-29 | 1982-08-10 | University Of Utah Research Foundation | Enhanced leaching of minerals which form product layers |
US5316751A (en) | 1991-02-11 | 1994-05-31 | Gordon Kingsley | Methods for mine tailing clean-up using recovery technologies |
US5492681A (en) | 1993-03-22 | 1996-02-20 | Hickson Corporation | Method for producing copper oxide |
US5908605A (en) | 1995-09-07 | 1999-06-01 | Henkel Corporation | Copper recovery process |
US5989311A (en) * | 1997-07-28 | 1999-11-23 | South Dakota School Of Mines And Technology | Recovery of copper from its sulfides and other sources using halogen reagents and oxidants |
FI121713B (en) * | 2009-06-26 | 2011-03-15 | Outotec Oyj | Procedure for dissolving calcopyrite concentrate |
MX2010000141A (en) | 2007-07-13 | 2010-03-15 | Metaleach Ltd | Method for ammoniacal leaching. |
EP2470680A1 (en) * | 2009-08-24 | 2012-07-04 | Metal-Tech Ltd. | Process for multi metal separation from raw materials and system for use |
CN102021325B (en) * | 2010-12-14 | 2012-07-04 | 深圳市格林美高新技术股份有限公司 | Method for respectively leaching copper and cobalt from copper and cobalt concentrate |
CN102688809B (en) | 2012-06-19 | 2013-04-03 | 昆明理工大学 | Ammonium-amine coupling activation method based on copper mineral sulfurization floatation system |
-
2015
- 2015-06-05 AU AU2015273208A patent/AU2015273208B2/en not_active Ceased
- 2015-06-05 US US14/731,944 patent/US9255308B2/en not_active Expired - Fee Related
- 2015-06-05 WO PCT/IB2015/001706 patent/WO2015189707A1/en active Application Filing
- 2015-06-05 PE PE2016002537A patent/PE20170111A1/en unknown
-
2016
- 2016-01-11 US US14/992,291 patent/US20160122847A1/en not_active Abandoned
- 2016-12-06 CL CL2016003152A patent/CL2016003152A1/en unknown
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102994747A (en) * | 2011-09-13 | 2013-03-27 | 郴州市金贵银业股份有限公司 | Technology for recovering metallic copper from high-lead copper matte |
Also Published As
Publication number | Publication date |
---|---|
US9255308B2 (en) | 2016-02-09 |
US20160122847A1 (en) | 2016-05-05 |
CL2016003152A1 (en) | 2017-09-08 |
AU2015273208A1 (en) | 2017-01-19 |
US20150354025A1 (en) | 2015-12-10 |
PE20170111A1 (en) | 2017-03-11 |
WO2015189707A1 (en) | 2015-12-17 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8388729B2 (en) | Method for ammoniacal leaching | |
EP2201145B1 (en) | Controlled copper leach recovery circuit | |
JPH0688147A (en) | Wet refining method | |
PL178355B1 (en) | Hydromechanical recovery of metals from complex metal ores | |
CA2470478C (en) | High temperature pressure oxidation of ores and ore concentrates containing silver using controlled precipitation of sulfate species | |
CA2927461A1 (en) | Leaching of minerals in the presence of lime and/or limestone and a complexing agent | |
CA2949036A1 (en) | Hydrometallurgical process for the recovery of copper, lead and/or zinc | |
JP2015214731A (en) | Gold recovery method | |
US10961633B2 (en) | Recovery of copper from copper-containing sulfide ores | |
US20090217786A1 (en) | Processing of laterite ore | |
AU2015273208B2 (en) | Methods of copper extraction | |
US7438874B2 (en) | Pressure oxidation leaching in the presence of an acidic solution of halide and sulfate ions from copper and base metal containing ore/concentrate | |
PL205892B1 (en) | Process of upgrading a copper concentrate | |
Wodka et al. | Pressure leaching of shale ore in oxygenated sulphuric acid | |
CA2994578C (en) | Hydrometallurgical method for silver recovery | |
CA3075464C (en) | Method for recovering cu and method of preparing electrolytic copper | |
US11584975B1 (en) | Integrated pressure oxidative leach of copper sulphidic feed with copper heap leach | |
AU2015268083B2 (en) | Method for ammoniacal leaching of copper from oxidised copper ores | |
Tinkler et al. | Copper solvent extraction on the African Copperbelt: From historic origins to world-leading status | |
CA2663356A1 (en) | Process for the indirect bioleaching of zinc sulphide | |
AU2007234509A1 (en) | Leaching of copper |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
FGA | Letters patent sealed or granted (standard patent) | ||
MK14 | Patent ceased section 143(a) (annual fees not paid) or expired |